Dean Pees wanted to believe nothing needed to change. This was the Ravens' defense, after all, and it isn't easy to overhaul a group that has long been one of the league's best.

It didn't matter that Ray Lewis and Lardarius Webb were out, that Terrell Suggs was playing on one leg, that Haloti Ngata had one healthy shoulder and one good knee. Or that the team's linebacker and secondary corps were so decimated by injuries that players were going from the practice squad to the starting lineup.

Regardless of who was out there, things would get better. For the season's first seven weeks, Pees was unwavering in that belief. But after the Ravens limped into their bye week following a 43-13 loss to the Houston Texans and with the NFL's 28th-ranked defense, Pees' patience officially ran out.

"The biggest problem that we had — and I take the blame for it — is trying to do exactly what we had done in the past without really looking at, 'Can these guys do what has been done in the past?'" said Pees, the Ravens' first-year defensive coordinator. "When you take over and you've been doing the same thing really for three coordinators in three years, you don't really want to change a whole lot of things up. … Then you start realizing that this is not quite the same group of guys that we had a year ago doing the same thing. After we got through that break, I think we really changed as a defense and for the better. Maybe I should have seen that a little earlier. I didn't but at least we saw it."

It is certainly not as dominant as the Lewis-led 2000 group that stormed into Tampa, Fla., and overwhelmed the New York Giants in Super Bowl XXXV to stake its claim as one of the best defenses ever. However, the current Ravens defense may be every bit as resilient, surviving a slow start and a slew of injuries to be in top form in the postseason.

Buoyed by the return of Lewis from a torn triceps injury, the Ravens stifled rookie phenom Andrew Luck and the Indianapolis Colts, 24-9, in the first round. They then went into Denver and forced three Peyton Manning turnovers and limited the high-powered Broncos to three offensive touchdowns in more than five quarters in a 38-35 double-overtime victory in the divisional round. The Ravens followed that up in the AFC championship game by shutting out Tom Brady and company in the second half en route to a 28-13 victory over the New England Patriots.

"We weren't a very fundamentally sound defense early on and that's why we had struggles," Ravens coach John Harbaugh said. "That doesn't happen overnight, and we were moving guys in and out. We had injuries. [Pees has] done a great job of making game-plan choices and decisions that have been really effective strategically against the people we've played. You saw that play out [against the Patriots]. Cary Williams mentioned that it was a pretty straightforward game plan, and it was. The guys executed it really well. To me, that's what a great coach, a great teacher does."

Pees, 63, will be coaching in his third Super Bowl. He went as the linebackers coach of the Patriots in 2004 and again in 2007 as New England's defensive coordinator. He said it was "special" to return to the big game, but he was more interested in crediting his assistants and the adjustments the players have made than dwelling on the circumstances that the Ravens have overcome.

How deep? On Dec. 16 against the Broncos, Josh Bynes, who spent the first six weeks of the season on the practice squad, started at middle linebacker and was the defense's signal caller.

"Actually, it's been fun," Pees said. "In some ways, it's challenging but in some ways, it's fun, too. You had to kind of figure out who you can put where and how you can use them. Sometimes, that's kind of fun rather than doing the same thing week-in and week-out. I'm not saying that I didn't want to have everybody back, but along with the challenge, it's kind of fun to draw some things up and try to do things a little differently and still try to get the job done."

The Ravens have gotten healthier as the season has gone on and that probably is the bigger factor in the defense's improved play. However, the players also credit Pees' steadying influence and his ability to teach rather than to blame. They say he did his best work following the Oct. 21 loss to the Texans.

That left the Ravens heading into their bye week with a 5-2 record but that was largely in spite of their once-proud defense, which was giving up an astonishing 400 yards per game, including nearly 143 yards per contest on the ground. Pees, the fourth defensive coordinator in Harbaugh's five seasons and the replacement for the extremely popular Chuck Pagano, predictably received much of the blame.

"Dean walks around kind of with that duck's back," Williams said. "The water gets on him but it just rolls right off his back. Great guy, great character, great coach. We believe in him because he believes in us. He never wavered. He never pointed the fingers at anybody. He took the pressure on his own back. It takes a lot of courage and a lot of manhood for a man to do that."

Changing the plan

When the team returned following the bye week, Pees told them that they'd get back to the basics. There was little yelling or finger pointing, just a whole lot of teaching.

"I thought we were asking guys to do maybe some things that they weren't particularly good at," Pees said. "But I also felt like we weren't as disciplined as a football team defensively as we needed to be early on either. There were some times that we had chances to make plays and our eyes weren't in the right spot, or we weren't in the right position. We corrected that and got a lot better at that."

Pees moved upstairs from the sidelines to the coaching box during games, speeding up the process of relaying the calls to the defense. He simplified several players' roles, like that of linebacker Paul Kruger, who is at his best as a pass rusher but struggled early in the season trying to replace everything that long-time Raven Jarret Johnson brought before leaving in free agency. Kruger took off with 10 sacks in his last 11 games. Ellerbe, the team's quickest linebacker, was unleashed, being used often to blitz. He was arguably the best Ravens' defensive player down the stretch.

Pees moved other players around, even using rookie linebacker Courtney Upshaw at defensive tackle at one point. He then frequently sought the input of players, meeting regularly with the team leaders to go over game plans.

"He's been the same demanding defensive coordinator as everybody else," Reed said. "There really hasn't been any change as far as attitude and how Chuck did things and our other coordinators with Rex [Ryan]. There really hasn't been a change as far as the demand he's required of us and he asks us things to make sure we know what we put in the scheme."

The Ravens finished the regular season ranked 17th in the NFL in total defense, allowing 350.9 yards per game and 21.5 points per game, the NFL's 12th-best mark. However, over their final six games, they have allowed 299 yards per game, fourth in the NFL during that span.

Against the Patriots in the AFC championship game, the Ravens held Brady to a 62.3 quarterback rating, the fourth worst in his 24-game postseason career. They also limited the Patriots' top-ranked red-zone offense to one touchdown in four trips inside the Ravens' 20.

As a result, Pees' reputation is on the rise. Four of the Ravens' six all-time defensive coordinators — Marvin Lewis (Cincinnati Bengals), Mike Nolan (49ers), Ryan (New York Jets) and Pagano (Colts) — have used the position as a springboard to a head-coaching job elsewhere. Pees, however, has no interest in such a jump.

"I do not want to be a head coach. I want to be a defensive coordinator," said Pees, who was the head coach at Kent State from 1998 to 2003. "It's why I got into it as a high school coach, because I like being around young people. I like having association with them, I like having fun with them. You become a head coach, you become everything but a coach. ... There are just so many other hats that you have to wear. I don't want to wear those hats. I want to wear this one right out here on the practice field, call defenses and play ball and have fun with the players."